Program Highlights

Development of Ultrasensitive Torque Magnetometer

We have developed the microcantilever torque magnetometer (MTM)—an ultra-sensitive technique for investigating the magnetic properties of nanostructures. To address the challenges of working with films nanometers (billionth of a meter) thick, we use a photolithography method to deposit a permalloy film (20 percent iron and 80 percent nickel) on the MTM (Figure a).

These permalloy films (Figure b) are about 30 nanometers thick with lengths and widths on the scale of a millionth of a meter. Though these materials are invisible to the eye, the fundamental physics of the magnetic interactions of these films are easily investigated by the MTM. Potential use of the MTM as a magnetic sensor has been demonstrated by its ability to clearly identify the magnetic switching of permalloy films.

This research was conducted in collaboration with the National Institute of Standards at Boulder. 

S.-H. Liou Group